Method for applying spacing means between electrodes of electric power sources



June 2, 1970 DQLL ET AL I 3,515,596 METHOD FOR APPLYING SPACING MEANSBETWEEN ELECTRODES OF-ELECTRIC POWER SOURCES Filed March 22, 1966 4Sheets-Sheet 1 J W ENIQ EOLL E HENRI DESIRE DRUESNE 0:4/ TTORN S3,515,596 TRODES June 2,1970 J. H. DOLL ET AL METHOD FOR APPLYING-SPACING MEANS BETWEEN ELEC OF ELECTRIC POWER SOURCES Filed March 22,1966 4 Sheets-Sheet 2 o o o o p o o o ooooqooo ca 0 o o o o o o 0 w l LC mm \8 8 a MU $74 3,

June 2, 1970 J. H. DOLL ETAL I 3,515,596 1 METHOD FOR APPLYING SPACING'MEANSBETWEEN ELECTRODES OF ELECTRIC POWER souncss Filed March 22, 1966 4Sheets-Sheet 5 28 m 80 2 I II LI 1J1; URLJIJIFLJLAXPI-GQ 26 ii \x\ w 2INVENTORS J EAN HENRY DOLL ggum DESIRE DR esuE. Y J ZTTQRNZS June 2,1970 I J. H. DOLL ET AL 3,515,596 Q METHOD FOR APPLYING SPACING MEANSBETWEEN ELECTRODES QF ELECTRIC POWER SOURCES Filed March 22, 1966 4Sheets- Sheet 4 ATTORN YS United States Patent 6 Int. (:1. Htllni 31/00,33/00 US. Cl. 136-175 9 Claims ABSTRACT OF THE DISCLOSURE A method foreffecting substantially uniform spacing between plates of cells of abattery comprising the steps of severing individual spacer elements froma spacing sheet, directly adhering the severed elements to an electrodesheet and stacking said sheets with additional electrode sheets, thespacer elements serving to provide the substantially uniform spacing.

This invention relates to apparatus and method for applying spacingmeans between electrodes of electric power sources such as deferredaction sea-water cells or batteries and fuel cells and to theirresultant products.

In primary or secondary electrical batteries and more particularly, indeferred action sea-water batteries comprising, for example, silverchloride-magnesium or cuprous chloride-magnesium couples, the separatormeans positioned bet-ween the positive and negative electrodes of eachcell must space and insulate the cathode from the anode of each cell,and at the same time allow for a rapid and sufiicient fiow ofelectrolyte therebetween, in order to make possible the evacuation ofelectrochemical and side reaction products (e.g., insoluble magnesiumhydroxide in the above-described batteries).

These conditions are ordinarily well filled by the use of quasi-punctualseparators comprising a plurality of small glass beads embedded on oneside of each positive electrode and having an excellent mechanicalresistance to pressure.

Such a battery is comprised of a stack of series-connected cells whichmust form a compact and strong unit. Therefore, the separator must havea sufiicient resistance to compression. Good compactness of thebatteries is usually maintained by means of an epoxy resin inserted onand between the peripheral rims of the cells.

However, many problems are created by the use of glass bead separatorsand their solutions are diflicult and expensive. Among these problems:

The tools required for embedding glass beads in the positive electrodescan only be used with one size of very uniform beads and must be changedif other size beads are to be used.

The distance between electrodes is determined by the size of the headbut allowance must be made for the necessity of embedding the beads inthe electrodes.

As a consequence, for each thickness of the silver chloride electrodedetermined by the electric specifications of the desired battery, thereis only one possible diameter for the appropriate beads. The distancebetween the electrodes of a cell, however, is not determined by theelectric specifications, but by the necessity of evacuating theinsoluble magnesium hydroxide created during its use. Thus, in order toassemble a short operational life battery, thin sheets of silverchloride about 0.1 mm., for instance, could be used, but as the distancebetween electrodes is required to be approximately always the same,about 0.5 mm., for example, it is impossible to embed =0.5O.6 mm.diameter glass beads in it. Moreover, for a battery of this type to bemounted in a torpedo, sea-water must be able to flow very quicklybetween the positive and the negative electrodes of each cell, hence theglass beads must be deeply inlaid in the silver chloride sheet.

With cuprous chloride instead of silver chloride electrodes, theabove-described problems are much more complicated and in realityWithout solution, because cuprous chloride is not maleable enough toretain the glass beads.

It is one object of the present invention to solve the above-describedproblems and difiiculties.

It is possible to find other attempted solutions described in therelevant literature:

One proposed solution is the incrustation in the two electrodessimultaneously of hard insulating bits, and then pressing one electrodeon the other after incrustation with said bits. In another proposed way,drops of glue or adhesive are sprayed at random on the surface of anelectrode and as a result, a number of insulating bits falling on theelectrode are adhered to it. This method is rather easy to carry out,but it gives indifferent results in electrical generators of thecharacter in question.

In another attempted solution, it has been proposed to apply aninsulating plastic composition in liquid form to the surface of theelectrode, and to cause said plastic to set and to adhere to theelectrode. In still another embodiment that has been proposed, theelectrode is first embossed to form spaced protrusions, the tips ofwhich are then covered with said liquid plastic composition.

In still another proposed solution, the electrodes have a number ofholes drilled therethrough into which polyethylene beads are inserted.

None of these processes or suggestions has yielded any interestingindustrial results because of the difficulties encountered in theirrealization.

It is to be noted that in the literature the desired separators aredescribed with much more accuracy than the manner of their practicalrealization because all the difficulties of the problems are preciselylocated in these manners of realization.

A suitable means for spacing cell electrodes embodying this invention,particularly for a deferred action sea-water battery is noteworthy inthat one face of each electrode of a given polarity is covered with aninsulating sheet, which is stamped by a cutting tool such as a die-platelaid over said electrode. The parts cut oif in the insulating sheet areautomatically fastened to said electrode and protrude from one side. Theremainder of the insulating sheet is then stripped from the electrode.

It is a further object and feature of this invention to fasten or securesaid deposited insulating parts to the electrode by gluing or welding orotherwise.

One way in which the stamped-out insulating parts may be secured to theelectrodes is that said insulating parts may, during their stamping out,'be pushed down or pressed into holes perforated beforehand in saidelectrode. They are then disposed during stamping out and pressing insuch a way that they protrude from the electrode on the opposite side tothat from which they have been pressed into it.

It can be seen, therefore, that with this embodiment of the process ofthe present invention, it is possible to secure insulating parts toelectrodes as by gluing, adhering, welding, soldering or by insertioninto holes in the electrodes. Obviously, any distribution of saidinsulating parts on the electrode surface can be chosen.

Said insulating parts, once fastened to the electrodes can be rolled,calendered or compresed after warming so that all have the same heightabove the electrode surfaces and can eventually be hardened or set ifthey are comprised of thermosetting plastics or of asbestos or,paperimpregnated with such plastics.

In a preferred embodiment, the insulating parts are fastened to thenegative electrode which is, for example, made of magnesium.

This form of invention is primarily concerned with primary or secondarybatteries or cells, particularly of the deferred action sea-water type,batteries of this type comprising at least one cell having a positiveelectrode of a silver chloride or cuprous chloride sheet, for example,and a negative electrode of a magnesium sheet, for example, saidelectrodes facing each other and being spaced from each other by thestamped-out insulating parts made of thermoplastic resin, ofthermosetting resin, or of a thermoplastic or thermosettingresin-impregnated porous carriers such as asbestos, paper, said partsbeing cut off or stamped out of a sheet of such materials and beingsecured to at least one electrode.

The fastening of the spacer parts on electrodes of one polarity or onboth electrodes at the same time is performed, for instance, as bygluing, welding as by heating, or by means of an adhesive, or by drivingsaid spacer parts with pressure into appropriate holes in an electrode.With the latter process, the insulating spacer parts driven into oneface of the electrode protrude from its other face and afterwards theylie in contact with the second electrode of the cell.

The above-described process for realizing separators is particularlysuitable for deferred action sea-water batteries. This process has beenfurther improved and with such further improvement or embodiments, it isnow possible to apply such improved process to solve much more diflicultproblems particularly relating to electrode spacing for fuel cells. Saidfurther improvements and solutions are further objects and features ofthe present invention.

In such further improvements, the spacer can be cut off from aninsulating or conductive sheet as desired and the stamped-out or cut-offinsulating or conductive spacer parts are then pushed and deposited ontoat least one face of each electrode of one polarity. That is to say, thespacer parts are cut or stamped out beforehand in an insulating orconductive sheet, for instance, as by drivers'or punches, and a cuttingtool in the form of a perforated die plate which is positioned betweenthe drivers and the electrode. Said spacing parts are secured to theelectrode as by gluing, welding, adhesion, insertion and stamping ontoor into holes in said electrode. The sheet from which the spacing partsare cut can be of an insulating material when said parts are to bepositioned between electrodes of different polarity and can be of aconducting material when said parts are positioned so as to connect twoelectrodes electrically.

It is a further object and feature of the present invention to choosethe shape, the location, the distribution and the number of drivers, andof the corresponding holes of the die plate in relation to the shape,the distribution in quality and the quantity of the spacer parts. Thesecomponents are chosen in order to provide a good flow of electrolyte andof fuel, particularly in relation to the gas diffusion and goodelectrical conductivity, mechanical strength, etc.

Other objects and features of the invention are the provision of adevice, apparatus or machine which makes the spacer part, said machineusing known tools, the arrangement of which is another object andfeature of the present invention.

Said tools are:

A number of drivers or rivet-like punches or the like, are secured to asupporting plate and operate in collaboration with a die plate, said dieplate having holes, the shape and the number of which are the same asthe drivers, said die plate comprising two parallel perforated platesspaced from one another by means which allows therebetween a receivingspace for the insulating or conducting sheet that is to be cut intodesired spacer parts to be deposited on the electrode. That one of theperforated plates which is the furthest from the electrode serves as aguide for the drivers, and the other perforated plate which lies justabove the electrode is a tool which cuts the spacer parts from the sheetand then guides the said parts out from the sheet and then guides thesaid parts out from the sheet to the electrode for deposition on orinsertion into the latter.

As it will be seen clearly hereafter, With such an apparatus or machine,it is possible to provide spacer means that quickly, easily andeconomically space the electrodes of electrical power sources of thetype described, providing at the same time very good operatingcharacteristics to the said power sources.

Further objects and features of the present invention are the provisionof primary or secondary batteries or cells produced by theabove-described improved process and/ or with the above-describedmachine, said batteries or cells being particularly of the deferredaction sea-water or fuel cell types, said batteries being particularlyremarkable in that each cell is composed of at least one positiveelectrode (e.g., of silver chloride, cuprous chlo ride, or a porouscarrier with catalysts on or in it) and of one negative electrode (e.g.of magnesium, or a similar porous carrier) facing and being spaced fromone another either by insulating spacer parts comprising thermoplasticor thermosetting resins, or porous carriers (e.g. asbestos, cardboard,paper) impregnated with such resins, said insulating spacer parts havingbeen severed from a sheet and secured to at least one of the electrodes.

In such batteries, two adjacent electrodes of adjacent cells belongingto different ones of such cells, may be series-connected as by a sheetof silver, for example, which serves at the same time as a partition toprevent intermingling of electrolyte between the cells of the deferredaction sea-water batteries, but they also can be series-connected byconductive spacer parts secured to at least one electrode having a metalpartition attached thereto.

Other objects and features of this invention will become apparent fromthe following description when considered in conjunction with theaccompanying drawings forming a part hereof and wherein:

FIG. 1 is a fragmentary enlarged sectional view of an electrode showinga manner of securing the insulating spacer parts to the electrode;

FIG. 2 shows a stack of electrodes spaced with the separator spacerparts in accord with FIG. 1 of the present invention;

FIG. 3 shows another embodiment of the combined electrode-separator ofthe present invention;

FIG. 3a shows a further sectional embodiment of an electrode-separatorembodying the invention;

FIG. 4 is a diagrammatical partly sectional view showing details of themain tools of a machine embodying the invention, in their initialpositions;

FIG. 4a shows a modified form of machine;

FIGS. 5, 6 and 7 are views similar to FIG. 4 of the machine of FIG. 4 insuccessive stages of its operation;

FIG. 8 is a plan view of an electrode provided With the spacer parts asembodied in this invention;

FIG. 8a is a fragmentary sectional view of another embodiment of suchelectrode;

FIG. 9 is a perspective view on an enlarged scale of a portion of theelectrode of FIG. 8;

FIG. 10 is a sectional view of a fuel cell embodying the presentinvention;

(FIG. 11 is a sectional view of a stack of parallel connected battery offuel cells using the spacer parts of this invention, and

FIG. 12 is a view similar to FIG. 11, but shows a stack ofseries-connected fuel cells embodying the invention.

Referring now to the drawings and first to FIGS. 1 and 2, the insulatingspacer parts 1, 1a, 1b, 1c, 1 1g, 1b of FIG. 2 are substantiallycylindrical in section. They are driven through the holes of thenegative electrode 2, 2a, 2b and 2c (of magnesium, for example). Thethree negative electrodes 2a, 2b, 2c are shown on FIG. 2. The holes 3provided in said electrodes into which the separating spacer parts 1,1a, 1b, 1c, 1f, 1g, 1h, as the case may be, are to be inserted, may bemade beforehand, for example, by a stamping or perforating press (notshown). The electrode plates 2, 2a, 2b and 2c may be, for example, a 0.4mm. thick magnesium sheet of desired configuration and holes 3 may be 1mm. in diameter. In stamping out the holes 3, the plates 2, 2a, 2b, and2c in the regions adjacent the holes 3 assume the flared sectional shapeshown in FIG. 1.

In an alternative embodiment, these holes 3 can be made by the same toolwhich inserts the insulating parts 1, 1a, 1b, 1c, 1 1g and 1h into saidelectrodes 2, 2a, 2b and 2c.

In still a further alternative embodiment, the said insulating parts arecut from the sheet of insulating material and then pushed into theflared mouths 4 of the holes 3 so that they protrude from the under sideof the sheets 2, 2a, 2b and as shown in FIGS. 1 and 2. They may then beriveted in place. The cells of the battery are seriesconnected so thatthe negative electrode 2a of one cell is in electrical contact with thepositive electrode 5b of the next adjacent cell. Generally, a thinconductive sheet 9a, for example, of silver is placed therebetweenelectrodes 2a and 5b to prevent the electrolyte from flowing betweensaid two electrodes which belong to ditferent adjacent cells,particularly when the electrodes are perforated by holes 3. Similarly, aconductive sheet 9b of the same material as sheet 9a is placed betweenelectrodes 2b and 5c. Thus, the superposed cells are series-connected,but are separated from each other by respective conductive sheets 9a and9b, the said sheets 9a and 9b being at the same time the currentcollectors.

Actually, a great number of flared holes 3 are provided in theelectrodes 2, 2a, 2b and 20, for example, one hole for each 5 to 10 mm.of electrode area in aligned or in staggered relationship.

The thickness of the insulating spacer parts 1, 1a, 1b, 1c, 1]", 1g and1h, that is to say, the thickness of the insulating sheet from whichthey have been cut is selected, depending on the flared form of thesheet 2 in order to: provide proper spacing between the electrodes ofeach cell.

The insulating materials from which said spacer parts are cut must havesuitable mechanical properties, particularly with respect to theirresistance to crushing, their elastic limits and their resistance toheat. Many materials may be suitable, for instance, thermoplastic resinssuch as polystyrene or thermosetting resins impregnating a porouscarrier such as paper, asbestos, etc., or similar insulating material.The polymerization of thermosetting resins may be efiected when needed,either before, or after fastening the insulating spacer parts to theelectrodes. Then calendering of the combined electrode and spacer partsmay be advantageous in providing uniform spacer depths or else inhardening the thermosetting resins if used for the spacer parts.

FIG. 3 shows one preferred embodiment of the present invention. Therein,the negative electrodes 6a and 611 (for example, of magnesium) and thepositive electrodes 7b and 7c (for example, of silver chloride), of apair of adjacent cells respectively are spaced and insulated from eachother in each cell such as that comprised by electrodes 6b, 7b of thestacked cells by the respective spacer parts 8a, 8b, 8c, 8d, etc. Twoadjacent plates 6a and 7b, 6b and 7c belonging to different adjacentcells are separated as by thin metallic sheets 10a and 10b, e.g., ofsilver.

The insulating spacer parts 80, 8b, 8c, 8d are secured to the respectiveelectrodes 6a, 6b, by gluing, welding, etc., They can be cut from asheet of plastic material which will stick to the respective electrodes,for instance, by heating, which fuses said material thereto or by anadhesive applied to the said material. The insulating sheet and theadhesive may be comprised of inert materials. It may be fiberglass,cardboard, paper impregnated with a resin that will be set chemically orbe thermoset by heating.

Said insulating sheet is placed on a special tool (a die press, forinstance, as will be described) so that insulating spacer parts can becut therefrom and then pushed directly onto the surface of an electrodewhich is positioned under the tool to receive them and which may beheated In assembling the batteries of FIGS. 2 or 3, the insulating parts1, 141, etc., or 8a, 8b, etc., are fastened to one electrode e.g.,electrodes 2a, 2b, 2c or 6a or 6b and in the stack of electrodes formingcells, they are simply laid against the adjacent positive electrode 511,5c and 7b, 7c of the respective cells. Obviously, however, they can besecured at the same time to the surface of both such electrodes.

A suitable machine for cutting spacer parts like 8a, 8b, 8c, 8d from aninsulating sheet and depositing them on an appropriate electrode, suchas 6a or 6b and the sequential steps in its operation is illustrated indiagrammatic section in FIGS. 4 to 7 inclusive.

According to the embodiment shown in FIGS. 4 to 7, a machine intendedfor embodying the spacer part forming and applying the process of thepresent invention comprises a driver or rivet-like punch carryingelement 11, said drivers or punches being designated 12. The element 11is advantageously composed of a backing plate 13 and of a carrying plate14 in which said drivers 12 are mounted for vertically reciprocalmovement.

The lowest ends of the drivers or rivet punches 12 are always engaged inaligned holes 15 of a plate 16 which latter serves as the guide elementof the die component 17, the second plate part 18 of which acts as acutting tool and which is spaced from plate 16 as by spacing members 19.The holes 15 and 20 of the respective plates 16 and 18 are, of course,in alignment with the drivers or punches 12. Below the die plate 18 astage plate 21 is located, being mounted on spring-like absorbers 22soldered or otherwise secured to a fixed base 23.

A laterally, reciprocally movable slide 24 with side jaws 25 whichlatter serve to fix an electrode, e.g., an electrode 6a, 6b or others towhich spacer parts are to be applied is slidable on the surface of thestage plate 21 as shown in FIGS. 4 to 7. A suitable stop member 26 islocated on the stage plate 21 to stop the slide 24 in appropriateposition under die component 17. Means of heating such as an electricalresistance heating coil 27 may be mounted in the slide 24. Thisresistance 27 could, of course, be replaced by another type heatingmeans, for instance, with a steam coil (not shown). The plates 16 and 18may be hollow so that cooling means, for instance, water, may becirculated through them as desired, entering through a pipe 28 andexiting through another pipe 29. The water can be admitted as desired tocool the die plates 17 and 18 when needed.

Between the die plates 16 and 18, the spacer members 19 provide a spaceor chamber 30' into which a sheet 31 of the desired spacing materialfrom which the spacer parts are to be out can be inserted. The thicknessof the sheet 31, is, of course, chosen according to the desired spacingdistance required between the electrodes of the cells and batteries tobe manufactured.

The operations of the machine are readily apparent from FIGS. 4 to 7.The machine being at the outset in the state shown in FIG. 4, anelectrode plate 6a or the like, is placed on the slide 24 and the jaws25 serve to lock themselves on the electrode plate rims when the slide24 is moved against the stop 26 locking the electrode plate 6a, 6b, asthe case may be, in position under the die plate 18 A spacing sheet 31is then inserted into the chamber 30 Then driver plate 11 is moved downand the drivers 12 out said sheet 31 as shown in FIG. 6 into separatespacer parts 8a or the like which are guided in the holes 20 of theplate 18. The drivers or rivet punches 12 are guided in their cuttingoperation by the guide plate 16 and by the die plate 18. All the cutspacer parts 8a or the like are pushed downwardly as shown in FIG. 7onto the upper surface of electrode plate 6a or the like and theadjusted biasing action of the spring means 22 provides a suitablepressure to secure the parts 8a on the electrode 6a or the like.

The distribution, the shape, the size and the number of the spacer parts8a or the like are chosen in relation with the electrolyte flow, thediffusion of gas, the electric conductivity, the mechanical strength,etc., which are desired for the battery to be formed.

In FIG. 8, an embodiment is shown in which the severed pellet-likespacer parts 32 are cylindrical in Lshape, the depth of each of which isthe thickness of the sheetil from which they have been cut or punched.This FIG. 8 shows a sea-Water battery negative electrode 33, thelocation thereon and the shape of the spacer parts 32 being chosen inorder to facilitate electrolyte flow as indicated by the arrows; that isto say, in order to insure a good distribution of electrolyte all overthe active surface of the electrode 33. For some purposes, some of thespacer parts 34 may have another shape as can be seen in FIG. 8. Thelatter are intended todeflect the electrolyte as it enters betweenelectrodes so as to provide a good distribution of electrolyte all overthe active surface of the said electrodes. These spacer parts 34 alsomay be cut off from the same sheet 31 as the parts 32, it being merelynecessary to modify the sections of some of drivers 12 and holes 15 andin which they operate so that spacer parts 34 rather than parts 32 willbe cut and deposited on the electrode.

In the case of FIG. 8, the spacer parts 32 and 34 are advantageously cutfrom or punched out from a plastic material sheet 31 coated beforehandon at least one face, with an adhesive product which will stick to theelectrode by use of heat. Said adhesive product must be chosen towithstand the operating conditions of the desired power source, that isto say, the internal temperature, the electrolyte, etc. For thispurpose, the adhesi e is advantageously of a polymeriza-ble type. It ispossible to secure the spacer parts 32 and 34 firmly on the electrode 33merely by heating the latter as by coil 27 and maintaining the driversor punches 12 in the position shown in FIG. 7 for a suitable time, thatis sufficient, for example, to the fuse and polymerize the adhesiveproduct on the electrode surface on which said parts 32 and 34 have beendeposited. Said adhesive product advantageously is in the form of atape, one face of which is adhered to the sheet 31 with nonpolymerizingheat, pressure, etc., and the second face of which is normally protectedby suitable cover sheet such as paper which is stripped therefrom justbefore its insertion into the machine space 30.

As a non-limitative example:

The spacer parts 32 are: cylindrical in shape, 1.1 mm. in diameter, 1mm. thick and are distributed on the surface of electrode 33 four persquare centimeter and are made of polypropylene.

The adhesive product constitutes a tape available commercially asScotch-weld" No. 583, one face of which is protected by a cover sheet ofstrippable paper. The other face of this tape is adhered to one face ofthe polypropylene sheet 31 prior to its insertion into the die space 30by pressure and heat which latter is insufficient to polymerize theadhesive tape. The protective paper cover sheet is stripped from thetape just prior to insertion of sheet 31 into die space 30, so that theexposed surface of the tape faces die holes 20. Then, as the drivers 12cut the parts 32 as described and deposit and press them onto the elec-8 trode 33, the heating of the latter effected by coil 27 is effectiveto adhere parts 32 to said electrode and is sufficient to polymerize theadhesive of the tape so that said spacer parts 32 are strongly securedto said electrode and resistant to the chemical action of seawater oreven of concentrated alkaline electrolyte solutions.

It is apparent that any suitable means can be used with the machineshown in FIGS. 5 to 7 to secure spacer parts to an electrode, amongthese are: gluing, welding, sticking by application of heat, or directinsertion of the cut spacer parts 32 by the drivers 12 into holes madebeforehand in the electrode, which are plugged or filled by the spacerparts as shown in FIGS. 1 and 2. The electrode 1 could even have holes 3stamped into it by the spacer parts 1 cut in the machine of FIGS. 5 to 7with suitable pressure applied to drivers 12. When said spacer parts 1are inserted into holes 3 of the electrode 2, they can advantageously besubmitted to a kind of riveting action as shown in FIG. 1 in order toplug said holes 3 and be secured therein.

In FIG. 9, a thin silver sheet can be seen under the magnesium sheet 33which forms the electrode; the sheet 35 must effect an electricalcontact with sheet 33 and also serve as a partition for the electrolytein an assembled battery.

Manner of securing spacer parts to electrode surfaces has been describedhereabove. It is clear that to secure the opposite faces of the spacerparts onto two sheets, it is enough to place the second sheet on saidspacer parts after they have been deposited on the first and then toapply the same pressure on them and the same heating temperature on theelectrode as has been previously done. This operation will be easier ifthe spacing sheet 31 has been covered with an adhesive tape on bothfaces prior to insertion into the machine of FIGS. 5-7.

In FIG. 10, the use of spacer parts 36 made according to the presentinvention are shown as spacing and insulating two electrodes 37 and 38of a fuel cell 39, in which C, is the comonrent and C the fuel.

The separating spacer parts 36 have been made by the same way as themeans 32. Of course, the material of the spacer parts 36 has. beenselected which is inert to the electrolyte 4ft flowing between theelectrodes 37 and 38 which are made of a porous material having therequired and suitable catalytic properties.

In FIGS. 11 and 12, fuel cells 41 and 42 having cells respectivelyconnected in parallel and series are shown. Therein, in FIG. 11, thespacer parts 43 are shown on the first-hand of insulating material,insulating two different polarity electrodes 44 and 45 and other spacerparts 46 on the second hand are of conductive material mechanicallyspacing and electrically connecting two adj acent-like polarityelectrodes 44. Similarly, in FIG. 12, the spacer parts 47 betweenelectrodes 48 and 49 of different polarity of the same cell are ofinsulating material, while spacer parts 50 are conductive.

Thus, separating or spacer parts 43 and 47 are made of an insulatingmaterial, whereas spacer parts 46 and 50 are of a conductive material.

The spacer parts 43 and 47 of insulating material are cut or punchedfrom a sheet of such material in the machine of FIGS. 5-7 and applied totheir electrodes as hereinabove described. Similarly, the conductivespacing parts 46 and 53* are cut or punched from a sheet of conductivematerial in the machine of FIGS. 57 and applied to their electrodes ashereinabove described.

In FIG. 11, the individual cells of the fuel cell 41 are shown as beingparallel-connected, whereas in FIG. 12, the individual cells of a fuelcell 42 are shown as being series-connected.

In FIG. 12, the partitions 51 between individual cells are made of ametallic conductive sheet, being at the same time current collectors forsuch cells.

Obviously, the distribution and the size of the spacer parts 43, 46, 47and 50 are chosen, particularly to promote the electrochemical Work oftheir cells, the gas diffusion for comburent and fuel, the flow ofelectrolyte 52 9 or 53, the mechanical strength of the stack of thecells 41 or 42, etc.

Thus, in FIGS. 8a and 12, a staggered disposition of insulating spacerparts 47 and conductive spacer parts 50 is shown. These spacer parts 47and 50 are secured at the same time on both facing faces of an electrode48. This may be accomplished in the machine of FIG. 4a. In this figure,all primed reference characters denote parts corresponding to those ofFIG. 4 and are located below them.

It is obvious that the sheets from which respective of the insulatingand conductive spacer parts are made is not the same.

Many variations may be applied to the above description, for example,the respective spacer parts 43 and 46 could be applied, at the same timeto the same electrode plates 45 or 44 by the machine of FIG. 4a. Thedepths of the respective spacer parts 54 and 55 applied to an electrode56 (see FIG. 3a) can be different in various areas thereof; such adisposition could be of interest, for example, for the magnesiumelectrodes of a deferred action sea-water battery, the areas near rimsof the said electrodes being covered with higher spacer parts than thosein the middle areas, in order to readily position the positive electrodewhich is not as large as the negative one at its correct location. Insuch event, the spacer parts deposited on the rim areas will not be cutoff or punched from the same sheet as that from which spacers depositedin middle areas are cut off or punched, and they will form a sort offrame for the positive electrode. At the same time, they could serve toeffect tightness or sealing between the circular rims of the electrodes,said tightness presently being realized now by use of a setting resin.

The process can be semi-continuous in order to operate with largesurface plates. The drivers or rivet punches 12 cut and punch a firstseries of spacer parts and return to allow the electrode 6a or the likeand spacer sheet 31 or the like to advance, and the sequential operationof the machine as shown in FIGS. -7, goes on and on. Therefore, thisprocess can be made fully automatic and can be used to operate on verylong electrodes such as band-shaped electrodes and continuous sheets ofspacer material, said band and sheets being advanced cyclically aftereach severance and deposition of spacer parts on a particular area ofthe electrode band.

Although specific embodiments of the invention have been described andshown, variations in practice within the scope of the appended claimsare possible and are contemplated. There is no intention, therefore, oflimitation to the exact disclosure herein presented.

What is claimed is:

1. A method for effecting substantially uniform spacing betweenelectrode plates of plates of cells of a battery comprising the steps ofproviding a sheet of spacing material coated on one face with anadhesive that becomes tacky when heated, inserting the adhesive bearingsheet into a cooled punching out device with the adhesive of the sheetmaintained in non-tacky state by such cooling facing away from thepunches, positioning a sheet of electrode material directly facing theadhesive in nontacky state bearing face of said first-named sheet,cutting out separate spacer elements from such first-named sheet withsaid device in any selected pattern and pushing the punched out spacerelements immediately after being cut out with their adhesive innon-tacky state bearing faces directly onto said electrode sheet whileheating the latter to render the non-tacky adhesive of said spacerelements tacky, and thereby directly and positively depositing andpressing the punched out spacer elements onto said electrode sheet towhich they then become adhered by the tackiness of the now heatedadhesive pressed onto said heated electrode sheet, maintaining heatingand pressure to effect permanent adhesion of the spacer elements to saidelectrode sheet, and subsequently superposing a second electrode plateover the spacer element bearing face of the first electrode sheet.

2. The method of claim 1, wherein said sheet of spacing material and theindividual spacer elements are nonconductive.

3. The method of claim 1, wherein some of the spacer elements havecylindrical shape and others have a different shape.

4. The method of claim 1, wherein the adhesion is effected by apolymerizable adhesive polymerized by heat after deposition of saidspacer elements on said plate.

5. The method of claim 1, wherein the spacer bearing electrode plate isa negative electrode and the second electrode plate is a positiveelectrode to form an electric cell upon adding electrolyte.

6. The method of claim 5, wherein said negative electrode comprisesmagnesium, and the positive electrode comprises a chloride selected fromthe group consisting of silver chloride and cuprous-chloride.

7. The method of claim 1, wherein said sheet of spacing material and theseparate spacer elements are insulative.

8. The method of claim 1 including the step of stacking a plurality ofsaid cells with the adjoining electrodes of adjacent cells havingopposite polarity and interposing a conductive, non-permeable sheetbetween said adjoining electrodes which prevents inter-mingling ofelectrolyte of the individual cells in the stack.

9. The method of claim 8, wherein said non-permeable sheet is silver.

References Cited UNITED STATES PATENTS 1,995,076 3/1935 Perryman 156-2523,015,884 1/ 1962 Chamberlain 29-432 3,180,009 4/1965 Lenz 29-4323,129,118 4/1964 Wilke et a1 136-100 3,156,586 11/1964 Solomon et al.136-100 3,228,803 1/1966 Little 136-145 3,275,478 9/1966 Rosser et al.136-148 3,282,734 11/ 1966 Rzewinski 136-86 3,306,775 2/1967 Burant etal. 136-90 WINSTON A. DOUGLAS, Primary Examiner O. F. CRUTCHFIELD,Assistant Examiner US. Cl. X.R.

